Two month old babies with smelly mouth is usually related to physiological factors such as unhygienic oral cavity, as well as pathological factors such as indigestion and oral diseases. 1. physiological factors: two months baby mouth stink may be because of long-term not pay attention to the baby’s oral hygiene, there are a lot of food residues, breeding bacteria and so on. 2. Pathological factors: two months baby mouth stink may also be due to indigestion caused by more food for a long time to stay in the gastrointestinal tract, fermentation produces a lot of gas, so there may be symptoms of bad breath; ulcers, herpes and other oral diseases, may lead to two months baby mouth stink symptoms. Two month old babies with smelly mouth, there may also be other reasons, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.